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Homework Help: Lagrange multipliers Problem

  1. Jun 3, 2007 #1
    1. The problem statement, all variables and given/known data

    find the max and min of f(x,y)=x^2y, constraint x^2+y^2=1

    2. Relevant equations


    3. The attempt at a solution

    I found that possible points use the procedure of the method of lagrange multiplier, I got [tex](\pm\sqrt{2/3}, \pm\sqrt{1/3}[/tex] so 4 points total.
    But do I have to check the end point on the constraint? like points (-1, 0), (1, 0), (0, 1), (0, -1)?

    and y this latex thing won't work? help plz. lol
    Last edited: Jun 4, 2007
  2. jcsd
  3. Jun 4, 2007 #2
    You should check the boundaries because for 1) they could have max or min depending contexts and 2) they will give you some sanity towards the answer you have.
  4. Jun 4, 2007 #3
    Change the direction of the slash on your closing tex tag. [\tex] sould be [ /tex] (witout the space obviously)
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